In this issue of the Emergency Medicine Journal (EMJ) we have two papers exploring tools to predict critical illness in sepsis. Two retrospective cohort studies, in ED patients with suspected sepsis/infection, evaluate the diagnostic accuracy of the relatively novel qSOFA (Sepsis-3 2016) in comparison to existing sepsis prediction tools such as the National Early Warning Score (NEWS), SIRS and serum lactate measurements. The first multicentre US analysis of 3743 patients, by Rodriguez and colleagues (see page 350), compares qSOFA with existing tools in predicting death, vasopressor use or ICU admission within 72 hours of ED attendance. By demonstrating and improved, or similar specificity for the primary outcome across a range of scores, the authors conclude that qSOFA criteria performed as well or better than existing tools in predicting critical illness. The second single centre UK analysis of 1818 patients, by Goulden and colleagues (